- 1/2 gallon whole milk*
- 1/2 cup whole milk yogurt (with live cultures)
Place the milk into a pot and heat it until it just begins to bubble around the edges (180°F on a food thermometer). Allow the milk to cool to 110 to 115° F. (This will take a while at room temperature; to expedite the process, place the pot into a sink filled with ice water and stir the milk). Once the milk cools, stir in the yogurt. (Don’t stir it in before it reaches 115° F or the heat may kill the live cultures in the yogurt). The pot needs to rest in an insulated space where the temperature will remain at 110°F for at least 6 hours so the bacteria can multiply. (Try wrapping the pot in a towel and placing it on a hot pad; or place it into an oven that can be set to 110° F. ) Allow the mixture to ferment for at least 6 hours, or overnight. Refrigerate. For a thicker yogurt, line a wire mesh sieve with cheesecloth and strain the yogurt.
*Note: 2% milk can be used but will result in a runnier yogurt.